Hot-air furnace



S. P. KAY.

HOT AIR FURNACE.

APPLICATION FILED JAN. 15. 1921.

Patent ed Apr. 18, 1922.

INVENTOR :1

ZNEY I U iff a m tm M/n k9 7 a A 9 H 5W s Y T B A U /M\ W z I m H H. H HJ J m \v\ H a v 11 6 7 a H l m U 4 I P E w a for-the purpose of startingthe indicate like parts.

SAMUEL P. KAY, OF ROCHESTER, NEW'YORK.

HOT-AIR FURNACE.

Application filed January 15, 1921.

To all whom it may concern Be itknown that I, SAMUEL P. KAY, a citizenof the United States, residing at Rochester, in the county of Monroe andState of New York, have invented certain new and useful Improvements inHot-Air Furnaces, of which the following is aspecification.

The object of this invention is to provide a new and improved form ofhot air furnace which is especially adapted to burn hydrocarbon ineither liquid or gaseous form.

These and other objects of this invention will be fully illustrated inthe drawing, described in the specification and pointed out in theclaims at the end thereof.

In the accompanying drawing:

The figure shows a diagrammatic perspective view of the furnace and thesystem for controlling the regulation of the hydrocarbon into theignition chamber in conjunction with the opening and closing of thesmoke pipe damper.

In the drawing, like reference numerals The furnace illustrated in theaccompanyi-ng drawing is provided with a blower 1, which is adapted toforce a mixture of kerosene oil and air through the duct 2 into theignition chamber 3. This apparatus, however, forms no part of myinvention an -in its place any other system, of forced feed for ahydrocarbon fuel in either liquid, gaseoils or powdered form may besubstituted.

The duct. 2, carrying the fuel from the blower 1, leads into the chamber4, in which the ignition chamber 3' is mounted. The ignition chamber islocated in the chamber at a point which allows the flames from theignition chamber to enter the. opening in the bottom of the fire boxfrom the side of the fire. box 5 down on the outside thereof and intothe chamber 4, below the fire box, is the by-pass duct 6. This duct hasa-door 7 provided on the outside wall at a point opposite to the sectionof the duct leading out from the fire box.

Through this door the ignition chamber canv be reached from the outsideof fithe furnace re. The top of the fire box leads into the customaryheating duct 8 through which the hot gases travel in a circular patharound the inside of the shell of the furnace'to give off the heatgenerated by the fire in the fire box. After passing through the duct 8,the

gases enter the smoke pipe 9. This pipe is (1 switch opens the circuit wSerial No. 437,573

made up of several bent sections, the first of which leads upwardly fora short distance of about twelve inches above the exit of the duct 8.The next section leads horizontally to one sideof the exit of the duct8, then down in a long vertical path to a point on a level with or belowthe level at which the ignition chamber 3 is mounted on the inside ofthe chamber 4:. From this point, the pipe leads in a short, horizontalpath to one side of the vertical section of the pipe and then into thechimney 10 at this same level. In this way, a long path, made up ofseveral sections of piping, which include five bends that lead at rightangles to each other, must be traversed by the burnt gases after leavingthe duct 8 and before entering the chimney.

Mounted in the smoke pipe 9 is a damper. 11 which is operatedautomatically as will hereinafter be described. The blower 1 is drivenby an electric motor 12. The electric current for operating the motor iscontrolled by the thermostatic switch 13. This switch is placed at apredetermined point in the house that is to be heated by the furnace andoperates to close the electric circuit leading to the motor when thetemperature inthe house falls below a certain 'oint. This same en thetempera, ture rises above a predetermined point after the fire in thefurnace has been going for a length of time and heated the house to thetemperature indicated by the thermostat. Such a thermostatic control isnot new in the art of controlling the fire in a furnace so that only adiagrammatic view of the switch and the circuit is shown in thedrawshunted around the circuit that controls the motor 12 is a circuit14 which operates the solenoid 15. This solenoid in turn operates therack 16, which meshes with the pinion 17 carried on the pivot pin of thedamper 11. Thus, when the motorcircuit is opened and closed, thesolenoid circuit is also opened and closed and the damper 11 is movedtoopen the smoke pipe 9 when the motor 12 is started and then closes itpartially to prevent the escape of heat generated in the furnace whilethe 'fire in the furnace is going. On the closing the motor circuit, bythe thermostatic control, the solenoid is de-energized and allows therack 16 to drop and move the damper into the closed position. The heatabsorbed by the furnace Specification of Letters Patent. Patented Apr,.18, 1922,

5 nace is supplied by means of a forced feed.

A large quantity of air is thus forced into the fire box to furnish thenecessary oxygen for the combustion .of the hydrocarbon fuel. When thefire is started, the fuel is forced .10 by the blower into the ignitionchamber.

The air supplied to the blower for this purpose is taken from thevicinity of the furnace wherever the blower or its intake may belocated. This air is naturally at a low temperature and, therefore, whenmixed with the fuel proper prevents a complete combustion of the fuel.This results-in the eneration of smoke which is accompanied y an odor,that is objectionable in a dwelling house as there is usually no meansprovided in such a house that will carry off the smoke and the odor.

For this reason, the smoke pi e 9, leading from the furnace to the cimney, is

made to create a resistance to the passage of burning gases from thefire box in order to force the unburned gases, due to the incompletecombustion thereof, into the duct Gleading from the side of the firebox. This 3 duct leads the unburned gases down into the chamber 4 andback into the opening in the 1 bottom of the fire box where they areagain ignited and this time with a complete com- .bustion thereof. Thegases taken from the 85 fire box, are naturally heated to a hightemperature and when brought in contact with the burning fuel. in theignition chamber, assist in burning the fuel without gencrating smoke,due to a complete combus- 40 tion of the fuel.

The resistance offered to the burned gases leaving the fire box at thetop thereof, is due to the length and change in direction of the path ofthe smoke pipe as well as the entrance point of the smoke pipe intothechimney. This point of entrance is at a level with or even below theentrance of the fuel into the fire box so that the atmospheric pressureof the air in the chimney at the entrance of the smoke pipe is equal ,tothe atmospheric pressure of the air sur-' rounding-the furnace. Nonatural draft is, therefore, present in the fire box which would have atendency to carry the burned 56 gases without resistance from the firebox into the chimney. The point of entrance of the smoke pipe into thechimney and the curved path of the smoke pipe itself offer sufficientresistance to the burned or un- GO burned gases in the fire box to makethem enter into the duct 6 rather than pass off through the smoke pipe9. In this manner,

the unburned gases are not only completely burned on their re-entranceinto the fire box in doing so, made to give off more of their heat thatwould otherwise go to waste by entering the chimney too quickly after being burned in the fire box.

I claim:

1. In a hot air furnace, the combination of a' combustion chamber, aliquid fuel burner at the bottom of said combustion chamber, saidcombustion chamber having an opening in the side thereof, a duct leadingfrom the opening in the side of said combustion chamber and leading tosaid fuel burner, a heating or radiating duct leading out of the top ofsaid combustion chamber and a smoke pipe leading from said heating ductdown on the outside of said furnace to a point below or in line with thefuel burner on the inside thereof.

2. In a hot air furnace, the combination of a combustion chamber havingan opening in the bottom thereof,-a fuel feeding system leadin into theopening insaid combustion cham er, a radiating duct leading out of thetop of said combustion chamber, a jacket surrounding both saidcombustion chamber and said radiating duct, and a smoke pipe leadingfrom said radiating duct down on the outside of said jacket and into thechimney.

3. In a hot air furnace, the combination of a combustion'chamber havingan opening in the bottom thereof, a fuel feeding system leading into theopening in said combustion chamber, a radiating duct leading out of thetop of said combustion chamber, a jacket. surrounding both said'combustion chamber and said radiating duct,

a smoke pipe leading from said radiating duct down on the outside ofsaid jacket and into the chimney, and a by-pass leading from the side ofsaid combustion chamber to the bottom of said combustion chamber on theoutside thereof. 1

4. In a hot air furnace, the combination ofa combustion chamber, a fuelfeeding system adapted to feed fuel into the bottomof said combustionchamber, a radiating duct leadingout of the top of said combustionchamber, a jacket surrounding both said radiating duct and saidcombustion chamber, and a smoke pipe leadin tending first upwardly; thensidewardly, then downwardly again and then outwardly into the chimney.

In testimony whereof I afiix my signature.

SAMUEL P. KAY.

from. said radiatlng duct, said smoke pipe ex-

